Ok so it’s a vague question, but Elon’s answer is just boneheaded & further obliterates the myth that’s he’s an “engineering genius”
A 🧵 with a few examples of “electric rockets”
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A 🧵 with a few examples of “electric rockets”
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First you can use electricity to run the turbo-pumps on a chemical rocket. This is much simpler, easier to control, & cheaper than traditional rocket engines.
Rocket Lab’s Electron rocket uses 10 electric pump fed engines to reach orbit.
Is this an electric rocket?
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Rocket Lab’s Electron rocket uses 10 electric pump fed engines to reach orbit.
Is this an electric rocket?
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Another approach uses electricity to accelerate ions to enormous speeds. Ion thrusters are much more efficient than chemical engines.
Remember the DART mission that crashed into Dimorphos? It was propelled by a solar powered (electric) ion engine!
Is this an electric rocket?
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Remember the DART mission that crashed into Dimorphos? It was propelled by a solar powered (electric) ion engine!
Is this an electric rocket?
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Ion engines are so efficient that they facilitate robotic exploration of our solar system.
When we send humans to Mars, it may be an electrically powered ion engine that enables that interplanetary trip!
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When we send humans to Mars, it may be an electrically powered ion engine that enables that interplanetary trip!
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Is Elon mentioning Newton’s 3rd law to to say that rockets must expel propellant as reaction mass to move forward? (aka conservation of momentum)
This isn’t true either.
Solar sail spacecraft accelerate without any onboard propellant. IKAROS did in 2010. Does that count?
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This isn’t true either.
Solar sail spacecraft accelerate without any onboard propellant. IKAROS did in 2010. Does that count?
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In the future we have more “electric rockets.”
The ambitious Breakthrough StarShot project plans to propel a solar sail probe to 0.2c to reach Proxima Centauri. To do this it will use a massive 100 GW laser array.
Presumably these lasers will run on some form of electricity?
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The ambitious Breakthrough StarShot project plans to propel a solar sail probe to 0.2c to reach Proxima Centauri. To do this it will use a massive 100 GW laser array.
Presumably these lasers will run on some form of electricity?
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This beamed laser propulsion approach is really cool because it circumvents the “tyranny of the rocket equation.”
The energy used for propulsion is generated on Earth, so the spacecraft doesn’t have to carry tons of heavy reaction mass with it!
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The energy used for propulsion is generated on Earth, so the spacecraft doesn’t have to carry tons of heavy reaction mass with it!
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In the much more distant future it might even be possible to propel spacecraft using light!
A hypothetical photon rocket uses an enormous amount of energy to generate a coherent beam of light, which propels the craft using the momentum of photons!
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en.wikipedia.org
A hypothetical photon rocket uses an enormous amount of energy to generate a coherent beam of light, which propels the craft using the momentum of photons!
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en.wikipedia.org
My point is that there are lots of ways to make an “electric rocket” either with electric turbo pumps or Ion Engines or to use electricity to power lasers as propulsion!
Newton’s third law does not prevent this! We just need to be smart & innovative!
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Newton’s third law does not prevent this! We just need to be smart & innovative!
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